Sanad, Sherif M. H.; Ahmed, Mohamed S. Mohamed; Mekky, Ahmed E. M.; Abdallah, Zeinab A. published their research in Journal of Molecular Structure in 2021. The article was titled 《Regioselective synthesis and theoretical calculations of Bis(pyrido[2′,3′:3,4]pyrazolo[1,5-a]pyrimidines) linked to benzofuran units via piperazine spacer: A DFT, MM2, and MMFF94 study》.Related Products of 4637-24-5 The article contains the following contents:
Bis(enaminone), linked to benzofuran units via piperazine spacer, was prepared and used as a key intermediate in this study. It reacted for 8 h at reflux with two equivalent of 2-cyanothioacetamide in dioxane in the presence of TEA to give the corresponding bis(pyridine-2(1H)-thione) derivative The previous compound was reacted with two equivalent of iodomethane in methanolic sodium methoxide solution at reflux for 1 h to yield the corresponding bis(2-methylthiopyridine) derivative Boiling of the prior compound with hydrazine hydrate in pyridine at reflux for 12 h gave the precursor bis(3-amino-1H-pyrazolo[3,4-b]pyridine) derivative in a good yield. Next, a regioselective protocol was conducted for the synthesis of a diverse series of the target bis(pyrido[2′,3′:3,4]pyrazolo[1,5-a]pyrimidine) derivatives in good to excellent yields. The protocol involved the reaction of bis(3-amino-1H-pyrazolo[3,4-b]pyridine) with two equivalent of prop-2-en-1-ones in DMF in the presence of two equivalent of barium hydroxide at reflux for 5-7 h. To gain a better understanding of the regioselectivity observed in these reactions, DFT calculations were performed using B3LYP method and 6-31+G(d,p) basis set. The favored mechanism and the exptl. regioselectivity of this reaction were explained by calculations of activation energy, natural at. charge, Fukui indexes derived from d. functional theory, MM2, and MMFF94 calculations The current study demonstrated that using the previous computational tools, the regioselectivity of the applied reaction protocol could be correctly predicted. The experimental part of the paper was very detailed, including the reaction process of N,N-Dimethylformamide Dimethyl Acetal(cas: 4637-24-5Related Products of 4637-24-5)
N,N-Dimethylformamide Dimethyl Acetal(cas: 4637-24-5) belongs to anime. Nitrous acid converts secondary amines (aliphatic or aromatic) to N-nitroso compounds (nitrosamines): R2NH + HNO2 → R2N―NO. Some nitrosamines are potent cancer-inducing substances, and their possible formation is a serious consideration when nitrites, which are salts of nitrous acid, are present in foods or pharmaceutical preparations. Tertiary amines give rise to nitrosamines more slowly; an alkyl group is eliminated as an aldehyde or ketone, along with nitrous oxide, N2O.Related Products of 4637-24-5
Referemce:
Ether – Wikipedia,
Ether | (C2H5)2O – PubChem